Commercial icemakers, such as those in common use in restaurants, hotels and the like require a substantial amount of water and electrical energy in order to produce ice at the rates required by a commercial establishment. At the same time, sanitary considerations with respect to ice intended for human consumption on the one hand, and maintenance considerations on the other hand, require that the water used in ice machines be free of pathogens as well as being free of mineral contaminants. The latter tend to accumulate on the freezer plates and need to be removed at frequent intervals to maintain the efficiency of the machine.
Because icemakers make ice by spraying water onto electrically chilled freezer plates, a substantial amount of water is lost during each freezing cycle by failing to freeze before reaching the bottom of the freezer plates and exiting into the drain; yet a considerable amount of energy is expended in lowering the temperature of this lost water as well as of the water that does freeze.
Regarding the filtration and purification of the water used for icemaking, it is ideally done by reverse osmosis because that is the most thorough practical method of purification. Unfortunately, the reverse osmosis process is relatively slow and does not lend itself well to applications in which large quantities of water need to be purified in a relatively short time.